An examination has told to know Thai students’ performance and knowledge. Thai schools use score from examination for measurement knowledge and aptitude of students. Examination has made to see all of the students which each student has different. Examination may help students identify which items are not well learned, and thus enable more effective allocation of study time. An examination has made to see defect points and prominent points of students which will brought to direct to the point solution. For example, Son & Kornell ( 2008) shows that when students receive a chance to re-test. They spend longer than first test and edit to defect of first test. The second test has had defect to less more than first test. This research shows that when students know about their some mistakes and they back to solution with first test which will make to second test is better result. At the same times aptitude development which could observe from the examination. For instance, if you usually have to the best score in one subject that has shown you have aptitude with that subject. It helps to get a developing clear learning.